\documentclass{standalone}
\usepackage{tikz}
\usepackage{ctex,siunitx}
\setCJKmainfont{Noto Serif CJK SC}
\usepackage{tkz-euclide}
\usepackage{amsmath}
\usepackage{wasysym}
\usetikzlibrary{patterns, calc}
\usetikzlibrary {decorations.pathmorphing, decorations.pathreplacing, decorations.shapes,}
\begin{document}
\small
\begin{tikzpicture}[>=latex,scale=1.5]
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  \draw[semithick] (-1,1)--(1,1)--(1,-1);
  \draw[->,semithick](-1,1)--(.5,1); 
  \draw[->,semithick](1,1)--(1,-.5); 
\end{tikzpicture}
\end{document}